The goal of the study extension is to see whether the incretin hormone GIP increases insulin secretion in individuals with CF and normal glucose tolerance compared to individuals without CF and normal glucose tolerance. This study includes 3 or 4 visits.

The purpose of this research study is to examine and understand the various mechanisms that contribute to CFRD and gain a better understanding of potential means to treat CFRD. Participation will include 2-3 visits, home monitoring, and will last about 2 years.

The purpose of this research study is to learn more about Graves disease and PTC/Hypothyroidism, How it effects brain function and brain function changes after starting medical treatment.

Insulin therapy, commonly given as multiple daily injection therapy, is the only recommended treatment for Cystic Fibrosis Related Diabetes (CFRD). Traditional therapy for CFRD requires an intense daily effort related to diabetes care on top of the already burdensome management of Cystic Fibrosis. In this study, we will assess the safety and effectiveness of the iLet Bionic Pancreas, an automated insulin delivery system, which uses a continuous glucose monitor (CGM), an insulin pump, and a control formula that activates insulin delivery based on CGM glucose data.